Euphorbia plant named ‘Silvershadow’

ABSTRACT

A new and distinct cultivar of  Euphorbia  plant named ‘Silvershadow’, characterized by its upright, outwardly spreading and mounding plant habit; vigorous growth habit; freely branching habit; and numerous white-colored flowers.

Botanical designation: Chamaesyce hypericifolia.

Cultivar denomination: ‘Silvershadow’.

CROSS-REFERENCED TO RELATED APPLICATIONS:

Title: Euphorbia Plant Named ‘Silverfog’

Applicant: Uwe Leinert

Filed: Concurrently with this application (U.S. Plant patent application Ser. No. 12/313,684)

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct cultivar of Euphorbia plant, botanically known as Chamaesyce hypericifolia and hereinafter referred to by the name ‘Silvershadow’.

The new Euphorbia plant is a product of a planned breeding program conducted by the Inventor in Angelbachtal, Germany. The objective of the breeding program is to create new compact Euphorbia cultivars with freely branching habit and numerous flowers.

The new Euphorbia plant originated from an open-pollination made in June, 2006 in Angelbachtal, Germany of a proprietary selection of Chamaesyce hypericifolia identified as code number F-04-06, not patented, as the female, or seed, parent with an unknown selection of Chamaesyce hypericifolia as the male, or pollen, parent. The new Euphorbia was discovered and selected by the Inventor as a single flowering plant from within the progeny of the stated open-pollination in a controlled greenhouse environment in Angelbachtal, Germany in October, 2006.

Asexual reproduction of the new Euphorbia plant by vegetative cuttings in a controlled greenhouse environment in Rheinberg, Germany since August, 2007, has shown that the unique features of this new Euphorbia plant are stable and reproduced true to type in successive generations.

SUMMARY OF THE INVENTION

Plants of the new Euphorbia have not been observed under all possible environmental conditions. The phenotype may vary somewhat with variations in environment and cultural practices such as temperature and light intensity without, however, any variance in genotype.

The following traits have been repeatedly observed and are determined to be the unique characteristics of ‘Silvershadow’. These characteristics in combination distinguish ‘Silvershadow’ as a new and distinct cultivar of Euphorbia:

-   -   1. Upright, outwardly spreading and mounding plant habit.     -   2. Vigorous growth habit.     -   3. Freely branching habit.     -   4. Numerous white-colored flowers.

The new Euphorbia can be compared to plants of the female parent selection. Plants of the new Euphorbia differ primarily from plants of the female parent selection in the following characteristics:

-   -   1. Plants of the new Euphorbia are more compact than plants of         the female parent selection.     -   2. Plants of the new Euphorbia have smaller leaves than plants         of the female parent selection.

Plants of the new Euphorbia can be compared to plants of Chamaesyce hypericifolia ‘Silverfog’, disclosed in a U.S. Plant patent application filed concurrently. Plants of the new Euphorbia differ from plants of ‘Silverfog’ in the following characteristics:

-   -   1. Plants of the new Euphorbia are more vigorous than plants of         ‘Silverfog’.     -   2. Plants of the new Euphorbia have larger leaves than plants of         ‘Silverfog’.     -   3. Plants of the new Euphorbia have shorter flower bracts than         plants of ‘Silverfog’.

Plants of the new Euphorbia can also be compared to plants of the Euphorbia ‘Inneuphdia’, disclosed in U.S. Plant Pat. No. 17,567. Plants of the new Euphorbia differ from plants of ‘Inneuphdia’ in the following characteristics:

-   -   1. Plants of the new Euphorbia are more vigorous than plants of         ‘Inneuphdia’.     -   2. Plants of the new Euphorbia have smaller and narrower leaves         with shorter petioles than plants of ‘Inneuphdia’.     -   3. Plants of the new Euphorbia have shorter flower bracts than         plants of ‘Inneuphdia’.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The accompanying colored photograph illustrates the overall appearance of the new Euphorbia, showing the colors as true as it is reasonably possible to obtain in colored reproductions of this type. Colors in the photograph may differ slightly from the color values cited in the detailed botanical description which accurately describe the colors of the new Euphorbia

The photograph is a side perspective view of a typical flowering lateral plant of ‘Silvershadow’ grown in a container.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photograph and following observations, measurements and values describe plants grown in Rheinberg, Germany, under commercial practice during the winter in a glass-covered greenhouse with day and night temperatures averaging 22° C. and light levels averaging 4,500 lux. Rooted young plants were pinched one time about five weeks after planting and plants had been growing for 16 weeks when the photograph and description were taken. In the following description, color references are made to The Royal Horticultural Society Colour Chart, 1995 Edition, except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Chamaesyce hypericifolia ‘Silvershadow’. -   Parentage:     -   -   Female, or seed, parent.—Proprietary selection of Chamaesyce             hypericifolia identified as code number F-04-06, not             patented.         -   Male, or pollen, parent.—Unknown selection of Chamaesyce             hypericifolia, not patented. -   Propagation:     -   -   Type.—By vegetative cuttings.         -   Time to initiate roots, summer.—About nine days at 22° C.         -   Time to initiate roots, winter.—About 13 days at 22° C.         -   Time to produce a rooted young plant, summer.—About three             weeks at temperatures of 22° C.         -   Time to produce a rooted young plant, winter.—About four             weeks at temperatures of 22° C.         -   Root description.—Medium in thickness, fleshy, fibrous;             white in color.         -   Rooting habit.—Freely branching; dense. -   Plant description:     -   -   Plant form and growth habit.—Mounding plant habit; plants             upright to outwardly spreading; broad inverted triangle;             vigorous growth habit.         -   Branching habit.—Freely branching, usually about three to             five primary branches each with numerous secondary and             tertiary lateral branches developing per plant.         -   Plant height.—About 18 cm.         -   Plant diameter.—About 35 cm.         -   Lateral branch description.—Length: About 15 cm. Diameter:             About 3 mm. Internode length: About 2.8 cm. Strength:             Strong. Texture: Smooth, glabrous. Color: Close to 146A. -   Foliage description:     -   -   Arrangement.—Opposite; simple.         -   Length.—About 2.6 cm.         -   Width.—About 1.4 cm.         -   Shape.—Elliptical.         -   Apex.—Acute.         -   Base.—Attenuate to acute.         -   Margin.—Entire.         -   Texture, upper and lower surfaces.—Pubescent.         -   Venation.—Pinnate, arcuate.         -   Color.—Developing leaves, upper surface: Close to 146A.             Developing leaves, lower surface: Close to 146B. Fully             developed leaves, upper surface: Close to 147A; venation,             close to 147A. Fully developed leaves, lower surface: Close             to 147B; venation, close to 147C.         -   Petioles.—Length: About 1.5 cm. Diameter: About 1 mm.             Texture, upper and lower surfaces: Pubescent. Color, upper             and lower surfaces: Close to 146A. -   Inflorescence description:     -   -   Flower arrangement/habit.—Single rotate flowers arranged in             umbel-like compound terminal cymes. Very freely flowering             with numerous flower buds and flowers per plant. Flowers             face upright and outwardly.         -   Fragrance.—Not detected.         -   Natural flowering season.—Spring and summer in Germany;             flowering continuous during this period.         -   Flower longevity on the plant.—About ten days; flowers             persistent.         -   Flower diameter.—About 1.9 cm.         -   Flower depth (height).—About 1 cm.         -   Floral bracts.—Quantity/arrangement: Two; opposite. Length:             About 7.25 mm. Width: About 2 mm. Shape: Elliptical to             lanceolate. Apex: Rounded to acute. Base: Fused. Margin:             Entire. Texture, upper and lower surfaces: Glabrous; smooth.             Color: When opening and fully expanded, upper surface: Close             to 155D. When opening and fully opened, lower surface: Close             to 155D. Floral bract petioles: Length: About 2 mm.             Diameter: About 1 mm. Color: Close to 146B to 146C.         -   Peduncles.—Length: About 2.5 cm. Diameter: About 1 mm.             Strength: Strong. Angle: About 60° to 90° from vertical.             Texture: Smooth, glabrous. Color: Close to 146A.         -   Cyathia.—Length: About 4 mm. Diameter: About 3 mm. Shape:             Oval. Aspect: Upright. Color, immature and mature: Close to             144A.         -   Nectaries.—Quantity per flower: About four. Shape: Lunate.             Length: About 1 mm. Width: About 2 mm. Color: Close to 146A;             towards the apices, close to 155D.         -   Reproductive organs.—Androecium: Quantity: About four             stamens per cyathia. Shape: Oval, bi-lobed. Length: Less             than 1 mm. Color: Close to 158C. Pollen: Scarce. Pollen             color: Close to 158D. Gynoecium: Quantity: One per cyathia.             Pistil length: About 3 mm. Style length: Less than 1 mm.             Style color: Close to 155D. Stigma shape: Crested. Stigma             color: Close to 155D. Ovary color: Close to 144A.             Seed/fruit: Seed and fruit development have not been             observed on plants of the new Euphorbia -   Temperature tolerance: Plants of the new Euphorbia have been     observed to have tolerate temperatures ranging from about 12° C. to     about 40° C. -   Pathogen/pest resistance: Plants of the new Euphorbia have not been     observed to be resistant to pathogens and pests common to Euphorbia. 

1. A new and distinct Euphorbia plant named ‘Silvershadow’ as illustrated and described. 